Machine for coating the inner surface of containers



E. H. BARKER ETAL 2,229,631

Jan. 28, 1941.

MACHINE FOR COATING THE INNER SURFACE OF CONTAINERS 2 Sheets-She'et l Filed June l, 1959 Ffa. z.

Jan 28, 1941- K E'. H. BARKER Erm. 2,229,631

MACHINE FOR COATING` THE INNER'SRFACE OF CONTAINERS Filed June 1, 1959 2 sheets-sheet 2 'In venan;-

1Y0/fry Born @Mewm fiar/wry Patented Jan. 28, 1941 MACHINE Foa comme Tm: rNNEa SURFACE F ooNrAlNEas Edwin H. Barker, Meylan, Pa., and Harry Born, Merchantville, N. J.

Application June 1,1939, Serial N0. 276,770

, s claims.

Our invention relates to improvements in machines for coating the inner surface ofcontainers, such as cans and collapsible tubes, with a coating of protective material.

Heretofore in all such machines it has been impossible, except by very expensive mechanisms, to obtain a uniform coating, particularly at the lower edge of the container where a thick heavy ring of material accumulates. Said thick ring of material upon the container makes it diillcult to properly seal the container.

The object of our invention is to provide novel means for applying a coating of material of uniform thickness upon the entire inner surface of the container.

A further object is to provide a simple and eilcient means for removing the excess material from the lower edge of the container from which the excess material is drained. thereby eliminating the thick ring of material from the container.

A further object is to lprovide a novel form of support for the container, said support comprising a porous structure having a high degree of capillarity, through the pores of which the coating material will be drawn from the surface of the container adjacent to the points of contact between the container and the support.

Aiurther object is to construct a. novel work carrier forming a unit of an endless conveyor belt of a coating machine. Said work holder including a conical tube upon which the container support is detachably mounted, and through which the coating material is directed from a stationary nozzle into the container to be coated.

'I'hese together with various other novel features of construction and, arrangement of the parts, lwhich will be hereinafter more fully de- A scribed and claimed, constitute our invention.

Referring to the accompanying drawings: Fig. 1 is a vertical sectional view of the novel work carrier and container support.l 2 is an enlarged plan view of the container support shown in Fig. 1. Fig. 3 is a side elevation of Fig. 2.

Fig. 4 is a vertical sectional view of a dierent form of container support. Fig. 5 is a vertical sectional view showing a still different form of container support. Fig. 6 is a plan view of Fig. 5. Fig. 'I is a front elevation of Fig. 1, with the container and container support removed. Fig. 8 is a plan view showing two work carriers with container supports thereon, anda container mounted upon one of said supports.

In the drawings in which like reference characters refer to like parts. I2 and I3 represent ,iz and is. 5

The plate I5 is provided upon its lower portion with a bearing I8, on which is supported parallel guide bars I3 and 20. An extension bearing 22 is mounted upon said bars and forms a support for a conical tube 23, through which tube the coating material is injected from a stationary nozzle 24, shown in Fig. 1, into the container 25 which is to be coated. Said container 25 is mounted upon the work carrier I4, immediately n, above the tube 23, with the lower open end of the container supported upon the container support, which latter surrounds the tube 23.

The injection nozzle 24 is arranged above a tank 26, containing the coating material, which 20 material is heated by suitable means not shown in the drawings.x A pump 21 is provided for forcing the material from the ltank through the nozzle 24 upon the opening of a control valve 23, adapted to be actuated by a. cam 29 formed 25 upon the bearing I3, of the work carrier, when the latter comes to rest with the inlet tube 23 above the nozzle 24. The tube 23 is conical and provides a large inlet opening at the lower end thereof which permits of slight variations in '30 the alignment between the tube 23and the nozzle 24. The conical tube 23 direotsthe coating material toward the relatively smaller outlet at the upper end of the tube.

A novel container support 30 is detachably 35 mounted upon the inlet tube 23, and is adapted for supporting the container 25 with the open end of the latter resting upon the support 30 and Aembracing the upper end of the tube 23. The coating material is injected by the nozzle 24 40 through the axial passageway formed through the tube 23 and the container support 30 for coating the inner surface of the container 25.

A V-shaped rest bracket 33 comprises arms 34 and 35 extending from a head 36, which latter is 45 slidably mounted upon the upper portion of the guide bars I9 and 20. Said head 36 has a tongue 31 extending between said bars and is adapted to be secured upon said bars by a clamp plate 33 and a screw 39 extending through the head 50 and engaging the plate 38. The container 25 is placed upon the support 30 and the upper portion of the container is adapted to be embraced by the arms 34 and 35.

The guide bars I3 and 20 are slightly inclined l5 from a vertical. line so that the container will the work carrier, when said plate `4|) is released -from cam mechanism, not shown in the drawings.

'Ihe container supports shown in Figs. 1 to 6 comprise porous structures, each provided with an axial bore adapted'to surround the tube 23, through which the c oating material is injected into the container 25. Said porous body forming said supportl provides means for removing the excess coating material from the container. The excess material willbe drawn .through the pores of the support structure by means of capillary attraction and gravity, and it will iiow down the outside surface ofthe tube 23 and drip into the tank 26.

The container supports are preferably in the form of cones adapting them for containers of different sizes. The supporting surface of the conical support is in contact with the lower inner e'dge of the container 25, and said supporting surface is porous, and consists of closely spaced points of support with capillary apertures formed between said points of support, through which apertures the excess coating material is drawn from the surface of the container which is in contact with said points of support, thereby removing the thick ring of material from the lower edge of the container.

The container supports shown in Figs. 1 to 6,

and 8, `are constructedwith supporting surfaces 45, in the form of wire mesh, or screening, hav- Ying capillary apertures through whichthe excess coating material is removed from the container 25.

The wiremesh cone shaped member is mounted upon a sleeve 46, which is adapted to be 'detachably mounted upon the inlet tube 23. A

disk 48 is secured to the sleeve 46, as shown in Figs. 1 to 3. 'I'he member 45 is secured at its base to the periphery of the disk 48, which latter has an upwardly turned flange 41 to which the lower edge of said member 45 is secured. The truncated top of the member45 is secured to the upper portion of the sleeve: 46 by soldering or brazing. The disk 46 is provided with holes 49, through which the excess material freely passes.

The container support 50, shown in Fig. 4, is similar to that shown in Figs. 1 to 3, with the addition of an inverted conical member 5|, also formed of wire mesh, with its truncated lower portion converging with and secured upon the lower portion of the sleeve 46, for directing the coating material from the periphery of the disk 52 toward the axis of the sleeve 46, so that it will flow down the tube 23 and tend tereduce the splashing of the material as it drips into the tank 26.

The supporting surface 45 s formed of closely spaced points of support throughout said surface,

and said surface is provided with capillary apertures formed between said points of support.4

The lower open end of the container 25 rests upon saidpoints of support, and the capillary apertures insure the complete drainage of the coating material from the inner surface of the aaaaesl The container support 60, shown in Figs. 5 and 6, comprises a -relatively thick conical sleeve 6|, formed of iron, or like material adapted for retaining heat. A conical member 62, formed of wire mesh; is mounted in spaced parallel relation with the outer conical surface of the sleeve 6|. 'Ihe wire mesh cone 62 is made in segments, each having radially positioned edge portions 63, projecting inwardly, and secured in grooves 64 formed in the outer conical surface of the sleeve 6|, by means of locking rods 65. 'Ihere is an annular space formed between the cone 62 and the outer surface ofthe sleeve 6| for the excess coating material to ow from the inner surface .of the container 25 when the latter is resting lower portion of the tube 23. The sleeve 6 I forms a heat retaining body which assists the ow of the excess material through the wire mesh cone 62 from the surface of the container 25 which is in contact with the cone 62.

The operation of the machine is as follows: The conveyor Ibelt is moved intermittently, the containers are placed with their open ends upon the container supports and the upper portionsv of the containers embraced by the arms of the work rest brackets on the work carriers. As the belt advances the Work carriers, the spring plates 4|I are lowered upon the containers and close the Vopenings in the necks of the containers andalso hold the containers upon the work carriers.

The coating material is heated in the tank and placed under pressure by the pump, the cori-` trol valve is opened when inlet tube 23 is at rest directly above the nozzle. The coating material is injected upwardly through the axis of the container support andthe tube 23 into the container for coating the inner surface of the latter. The excess material falls by gravity upon the porous container support and it is absorbed thereby, very much as a piece of blotting paper absorbs liquid. As the Work carrier is moved from above the nozzle the excess material ows from the container through the porous container support and drips into the tank to be reheated v'and used again.

The coating machine constructed as above described permits the use of a small quantity of the heated coating material, thus reducing the danger offire and the possible injury to the operat'ors, andsthe small quantity of material can .bemaintained in proper working condition at a low operating cost.

Various changes in the construction and arrangement of the parts may be made Without departing from our invention.

We claim:

l. A container support for machines for coating the inner surface of containers, comprising a body having a conical surface upon Whichmthe lower edge portion of the container is adapted to be mounted, said body having closely spaced points of support formed throughout said surface adapted to engage the container, said body having capillary pores located between said points of support adapted for the passage of excess material from the container through said pores, and said body having an axial bore through which the coating material is adapted to be injected into the container.

2. A container support for machines for coating the inner surface of containers, comprising an axially positioned sleeve, a` truncated cone formed of wire mesh surrounding said sleeve and forming an annular support for the container, and means for securing the cone upon the sleeve.

3. A container support for machines for coating the inner surface of containers, comprising a sleeve through which coating material is` adapted to be injected into the open end of the container positioned above the sleeve, a truncated cone formed of wire mesh adaptedfor supporting the `container, a disk concentrically mounted upon said sleeve, means securing the base of said cone to the periphery of the disk, and

ing the inner surface of containers. comprising a sleeve, a structure formed of wire mesh surroundingsaid sleeve. said structure having a medial portion of relatively larger diameter than said sleeve, said structure having conical end portions tapering in opposite directions from said medial portion toward the `opposite endslof said sleeve, and means for securing the contracted end portions oi said structure to the sleeve.

5.V A container support for'machines for coating the inner surface of containers, comprising v a sleeve having anj'axial .bore through which the coating material is adapted to be injected into the open end of a container positioned above said sleeve, said'sleeve having an outer conical surface, a conical porous member adapted for sup-' 

